Another "custom sort" bug?

[Tracy Perry]

The most recent official release fixed on "custom sort" bug that I found, but apparently there is another that has raised it's head.  I have a custom field set to check whether a pipe manufacturer does custom pipes or not.  It works just fine on entry point of the data and on display of the data/fields

 

But, when I do a custom sort by, I have this box

As you can see, the custom field is present, but it IS NOT de-selectable.  You can try to slide the slider to the left but it will not de-activate it.  Makes the custom sort pretty much useless in this case as it will ONLY show the ones that make custom pipes... and I wanted a descending sort order of ALL entries but could not get that aspect.